NEETPhysicsRay Optics
Match List-I with List-II. List-I List-II (A) Effective Power of two thin lenses in contact (I) P₁ + P₂ (B) Effective Focal Length of two thin lenses in contact (II) f₁ f₂ f₁ + f₂ (C) Effective Magnification of two thin lenses in contact (III) m₁ m₂ (D) Effective Power of a convex and a concave lens of equal focal lengths in contact (IV) Zero Choose the correct answer from the options given below:
Options
- A(A)-(I), (B)-(II), (C)-(IV), (D)-(III)
- B(A)-(II), (B)-(I), (C)-(III), (D)-(IV)
- C(A)-(I), (B)-(III), (C)-(II), (D)-(IV)
- D(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
Correct answer
D. (A)-(I), (B)-(II), (C)-(III), (D)-(IV)
Step-by-step solution
When two thin lenses are placed in contact, their effective power is the algebraic sum of their individual powers: P_ net = P₁ + P₂ . The effective focal length f_ net is given by 1 f_ net = 1 f₁ + 1 f₂ , which simplifies to f_ net = f₁ f₂ f₁ + f₂ . The effective magnification of a combination of lenses is the product of their individual magnifications: m_ net = m₁ m₂ . For a convex lens (positive focal length f ) and a concave lens (negative focal length -f ) of equal focal lengths in contact, the effective power